Mario Gotze is running out of time to be Germany's saviour once again

Ninety minutes, 66 minutes, 50 minutes: Mario Gotze's time on the pitch at these Euros has steadily eroded in each game, just as Germany have begun to hit their stride. The Bayern Munich attacking midfielder is expected to line up again for the World Cup winners against Slovakia in Lille on Sunday, but he will have to do better -- a lot better -- if he's to last much beyond the half-time break. Increasingly loud calls for the inclusion of Schalke teenager Leroy Sane back home in Germany reflect wide dissatisfaction with Gotze's failure to make a telling contribution in the group stage.

Far from making a huge step toward resurrecting a career that has stalled since his winning goal in the World Cup final two years ago, Gotze has replicated his club form all too faithfully in France. Occasional flashes of brilliance haven't been able to lift his overall game above the mundane; the mercurial boy they once called, quite earnestly, "Germany's answer to Messi" has grown into a man who's playing as if he's shackled by an invisible ball and chain. He's lost both the explosive pace and confidence needed to beat opponents.

How long will Joachim Low continue to keep the faith? The Germany manager has done everything possible to coax strong performances out of the 23-year-old by backing him to the hilt before and during the competition. As soon as Marco Reus pulled out of the national team with an injury on the eve of the tournament, Gotze was installed as an automatic starter. Low publicly professed to trust him to deliver in the national-team dress after yet another difficult season as a bit-part player with Pep Guardiola's Bayern.

Gotze needed "a coach that wants him in his team unconditionally," Low explained. Guardiola certainly wasn't that coach, and Carlo Ancelotti, who'll take over at the Allianz Arena at the beginning of next month, certainly isn't that coach, either, as we now know. The Italian told the the player in a telephone conversation a few weeks ago that he couldn't expect to be in the first team.

Much to Bayern's surprise, Gotze refused to take the hint and vowed to change Ancelotti's mind in the last year of his four-year contract. Munich executive chairman Karl-Heinz Rummenigge said that Gotze's stance was "difficult to evaluate," a nice euphemism for: "What in heaven's name is this guy playing at?" Gotze needed to make up his mind whether he wanted "to play continuously," Rummenigge warned, leaving little doubt that the German champions were intending to sell the former Borussia Dortmund prodigy before the new season starts.

Low and national team general manager Oliver Bierhoff were concerned that Gotze could be unsettled by the unsure outlook. "There should be no more interference from Bayern during the tournament," Bierhoff demanded sharply.

The club have been quiet since, but the situation remains complicated. Gotze has parted ways with his agent Volker Struth, who had been been plotting escape routes for the player back to Dortmund or to Jurgen Klopp's Liverpool. The player's father has told Der Spiegel that Mario feels that he can change the minds of Ancelotti and Bayern when he returns to the Bavarian capital from France.

Mario Gotze's minutes at Euro 2016 have diminished in each of Germany's three games thus far.

The club would be much happier to cash in now and save €12 million in annual wages than see him leave for free next year. There's a rumour doing the rounds in Dortmund that Borussia are trying to secure his services as a free agent for the 2017-18 season, just like Bayern did with Robert Lewandowski, the Polish forward who ran down his contract at the Signal Iduna Park in 2014.

It's hard to say whether Gotze is affected by the hazy outlook. Between games, he has cast a relatively happy figure in Germany's base camp Evian, brushing off criticism with a witty one-liner: "Sometimes you're the dog, sometimes you're tree." In Brazil, he was so unapproachable that reporters gave up talking to him altogether. But he's been markedly more relaxed in France, seemingly intent to dispel the impression that he's arrogant.

He's even joked with Der Spiegel reporters about going away to do some more ambush marketing for his sponsor Nike after an interview with the Hamburg-based magazine. He infamously wore a shirt with a big swoosh when he signed his contract in Munich in 2013, causing consternation at Bayern's board level. Ten percent of the club are owned by sponsors Adidas, who have also been long-term partners of the German Football Association. The incident stoked suspicions that Gotze's image was shaped by his management, not to his benefit. Recent publicity tweets for a TV manufacturer also seemed ill-advised, but they've stopped now that a new publicity team has been put in charge since his ways have parted with Struth.

There's yet time for him to cut through all of these distractions and be Germany's hero once more. But not much.

Raphael Honigstein is ESPN FC's German football expert and a regular guest on ESPN FC TV. He also writes for the Guardian. Twitter: @honigstein.